Answer: A. Only the strongest animals survive.
The theory of natural selection - the survival of the fittest suggests differential survival and reproduction of the organisms. This means the organisms that have better phenotypic advantage over the others likely to survive and reproduce in the adverse environment. Such phenotypic traits will be passed from the parents to the offspring and will promote the evolution of the species.
On the basis of the above description, the only the strongest animals will survive is the correct option.
